The service aspects of the Resource have been mainly focused on serving the needs of the collaborative research projects supported, but not funded, by the Simulation Resource grant. These include 2 PO1's and 5 RO1's, 1 R37 and 3 foreign-funded projects with 10 cardiovascular projects, 1 pulmonary projects, and 2 projects related to other organs and to cancer. In addition to these installations for collaborative projects, SIMCON was ported to the Silicon Graphics workstation and installed at the University of Illinois. This installation will be used in teaching of simulation methodology. Two installations to be used in biomedical research were made at Vanderbilt University. In addition to these software installations, we also continued to provide consultation on modeling issues, software products and the UNIX operating system to our collaborators and to a number of investigators at the University of Washington. We have provided continuing access to computing hardware to collaborators who do not have the hardware required for modeling and to outside groups for special projects. During the last year there has been continued emphasis on the documentation and archiving of software developed within the Resource. A new version of SIMCON (version 2.8.1) and new versions of MMID4 (version 2.1) and MSID4 (version 2.1) were installed. The FORTRAN code for the programs has been extensively modified and modularized. While this will not directly affect users of the model, it will ease future maintenance by expediting bug fixes and the incorporation of requested enhancements. It will also make the code more understandable to users who want to customize applications of the programs. Postscript versions of these programs are available for downloading from NSR. An important aspect of our effort is in the instruction on quantitative analysis of physiological systems. The clarification of what are the physiological processes has proven to be of more fundamental benefit to users of the resource than the specific models.